Paleoceanographic change in the Middle Ordovician of Argentina

Dr. Miles Henderson

Univ. of Texas of the Permian Basin

Abstract:

The Great Ordovician Biodiversification Event, the largest sustained increase in the diversity of marine organisms in the Phanerozoic, was likely driven by changing nutrient fluxes in the Ordovician ocean. Greenhouse conditions of the early Paleozoic are associated with distinct geochemical gradients between shallow and deep-water environments, leading to the expansion of nutrient rich anoxic deep-water. Reorganization of ocean circulation patterns associated with the transition from greenhouse to icehouse conditions in the Middle-Late Ordovician would have enhanced mixing between nutrient rich deep-waters and shallow surface waters. Evidence for enhanced mixing is observed worldwide as the Middle Darriwilian carbon isotope excursion, or MDICE, which reflects increased primary productivity in surface waters. The MDICE also coincides with a large drop in the Sr-isotope composition of the ocean, suggesting a link between Sr-isotope values and oceanographic change. Middle Ordovician carbonate rocks representing distinct environments deposited along a deepening slope from the Precordillera of Argentina are used to evaluate the potential for geochemical gradients and evidence of ocean mixing.

Bio: Dr. Miles Henderson is an Assistant Professor of Geology at UT Permian Basin where he teaches courses in sedimentary geology. He earned his Ph.D. in Geology in 2018 from the

University of Tennessee, Knoxville working on reconstructing oceanographic events from Middle Ordovician carbonates and black shale. He previously worked as a geologist in environmental consulting after earning his M.S. in Geology in 2008 at the University of Tennessee, Knoxville working on the biogenicity of the Precambrian macrofossil Grypania spiralis. He completed a B.S. Geology at the University of Georgia in 2008 and an A.A. at Georgia Perimeter College in 2005.

Luncheon is sponsored by Borehole Image Specialists

Bookings

Note: You are not required to log in to register for this event. If you do not wish to log in, simply use the form below to complete event reservation.

Bookings are closed for this event.